You have to trust any place you send your traffic, but I trust Cloudflare more than Google simply because of their business model. People get too caught up in "evil!" but it's simply about business models and how likely a business is to bend towards unethical behavior to stay in business, or continue to grow revenue/profits.

Cloudflare doesn't need to analyze my data to make money -- they offer a great service that people will throw money at them to use.